House Republicans launched a tirade Wednesday at Obama administration regulations, reversing what had been an unusual display of unity hours earlier at the president’s State of the Union speech.

In one of the first hearings of the Republican-run Congress, GOP lawmakers accused unelected administration bureaucrats of issuing rules that cost American jobs. Democrats insisted those same regulations protected public health and the environment, saved the U.S. auto industry and lessened dependence on foreign oil.

The sole witness before the House Energy and Commerce investigative subcommittee, administration regulation chief Cass Sunstein, reminded Republicans that “job creation is in the first sentence” of President Barack Obama‘s recent executive order to review all government regulations.

Business groups and Republican allies have complained bitterly that regulations implementing new health care, toxic emissions and financial overhaul laws, among others, are holding back hiring and economic growth.

Tuesday night, Republicans and Democrats sat together for President Barack Obama’s State of the Union speech to demonstrate unity following the assassination attempt against Rep. Gabrielle Giffords, D-Ariz. On Wednesday, partisanship was back to normal, and the hearing raised questions about whether the two parties can work together as the president suggested in his speech.

The chairman of the subcommittee, Florida Republican Cliff Stearns, went on the offensive at the outset, accusing the Obama administration of a “rush to regulate” and issuing job-killing regulations based on political correctness.

He said the administration of George W. Bush objected to regulations from nearly two-dozen agencies while the Obama administration has objected to none.

For much of the hearing, lawmakers from the two parties were talking more to each other than the witness — who often was cut off by Republicans who wanted to use their five minutes of question time to make statements condemning the administration.

Stearns demanded that Sunstein answer yes or no to his questions, frequently stopping the witness’ attempts to defend rules by the Environmental Protection Agency and other federal departments.

Rep. Diana DeGette, D-Colo., said that unlike the Republicans, she “would like to hear answers to some of these questions.”

Defending proposed environmental rules on controlling boiler emissions and greenhouse gases, she asked Sunstein whether the rulemaking allowed comments from the public and especially from industry.

“Yes, and it continues,” Sunstein said.

“Over 4,800 comments, including a large amount from industry,” DeGette said.

“Yes, I’m aware of the sheer volume of comments,” Sunstein replied.

Democratic Rep. Edward Markey of Massachusetts commended the administration, saying it saved the U.S. auto industry with stricter mileage standards that produced fuel-efficient cars that Americans wanted to buy.

He said limits on harmful emissions into the environment increased jobs in clean energy fields, in addition to saving the cost of treating environment-based illnesses and cleaning up environmental damage.

“We all know what the reality of this hearing is,” Markey said. “Republicans hope they can . turn the United States into a health, environment, safety and consumer protection regulation-free zone.”

Asking Sunstein whether industry often overestimated the cost of regulations, he replied: “Often that is the case.”

Stearns, tongue-in-cheek, said he knew that Markey was a baseball fan and complained the Democrat was asking Sunstein “a lot of softball questions.”

Rep. Phil Gingery, R-Ga., a physician, accused the administration of issuing a “dead of night” rule that included — in provisions for an annual Medicare wellness visit — references to end-of-life counseling. He said there was no chance for public comment.

The provision has come and gone.

The original House version of the health care overhaul legislation allowed for end-of-life discussions every few years. But the plan was dropped after Sarah Palin and other Republicans raised the specter of “death panels” deciding the fate of vulnerable seniors.

End-of-life counseling unexpectedly surfaced again late last year in a Medicare regulation that spelled out what would be covered in the new annual checkup, or wellness visit. Issued without fanfare, the regulation said such voluntary doctor-patient discussions could be part of the annual visit.

The administration this month decided to drop the end-of-life counseling references before the House voted to repeal the new health care law.

Rep. Fred Upton, R-Mich., who chairs the full Energy and Commerce Committee, told Sunstein he was worried about an Environmental Protection Agency plan to regulate emissions from large boilers that by court order may be issued soon.